Big Problems

Been trying to upgrade to Home Premium from xp, but have been having massive
problems.

I get a blue screen and this error:

STOP: c000021a {Fatal System Error}
The initail session process system process terminated unexpectedly with a
status of 0x00000000 (0xc0000001 0x0010034c)
The system has been shut down.

I've tried everything: Upgrade install, clean install and formatted the hard
drive.

I'm now without a pc so any help would be great.

Thanks